Writing method for multilayer optical disc

Abstract

A writing method for a multilayer optical disc. The method includes: measuring and recording optimum internal gains obtained when the objective lens is located on each inner side of the pick-up head, respectively, checking the writing direction based on the specific writing direction on each data layer of the disc, selecting the inner optimum internal gain when the writing direction is toward outside, and selecting the opposite inner optimum internal gain when the writing direction is toward inside to minimize the offset of the tracking error signal.

Description

[0001]This application claims the benefit of Taiwan application Serial No. 98127668, filed Aug. 17, 2009, the subject matter of which is incorporated herein by reference.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The invention relates in general to an optical disc drive, and more particularly to an optical disc drive which writes data on data layers in a multi-layer optical disc along different writing directions.[0004]2. Description of the Related Art[0005]Optical disc drive emits micro spots whose diameter range 0.85˜2.11 μm on an optical disc, and accordingly receives a reflection light from the optical disc. The electrical signal, formed by the difference in the amount of the reflection light, further controls the optical disc drive to read data along the data tracks on the optical disc. Since the reflection spots are very tiny, the electrical signals converted from the reflection spots are also very weak. To stably control the tracking to improve writing qu...

AI Technical Summary

Benefits of technology

[0008]One aspect of the invention is directed to a writing method for writing a multi-layer optical disc. Based on the optimum internal gains obtained when the objective lens are on sides of the pick-up head, respectively, the offset of the tracking error signal, which occurs when the objective lens is moved off the center of the pick-up head, is minimized.

[0009]Another aspect of the present invention is directed to a writing method for writing a multi-layer optical disc. According to the writing direction on each data layer of the optical disc, one from the optimum internal gains is selected for enhancing the stability of writing on each data layer.

Problems solved by technology

Since the reflection spots are very tiny, the electrical signals converted from the reflection spots are also very weak.

Consequently, writing on the optical disc is negatively affected, and the signal quality and the reliability are deteriorated.

Thus, there still have many problems occurred in writing on data layers of the multi-layer optical disc.

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